Radiosensitizing effect of carboplatin and paclitaxel to carbon-ion beam irradiation in the non-small-cell lung cancer cell line H460

Carbon Ion Radiation Therapy with Pencil Beam Scanning for Stage III Non-Small Cell Lung Cancer: Toxicity Profiles, Survival Outcomes, and Prognostic Indicators

PURPOSE

To evaluate the toxicities and survival outcomes associated with carbon ion radiation therapy (CIRT) using pencil beam scanning (PBS) technique and to assess the prognostic factors for patients with stage III non-small cell lung cancer (NSCLC) using a local effect model (LEM)-based biological dose calculation.

METHODS AND MATERIALS

This analysis included patients with stage III NSCLC (n = 181) who received CIRT between December 2016 and June 2023. CIRT was administered at a relative biological effectiveness-weighted dose of 77 Gy (range, 69-83.6 Gy) in 22 fractions (Fx) (range, 19-24 Fx). Most patients (96.1%) underwent systemic therapy before and/or after CIRT. Toxicities and survival outcomes were recorded, and statistical analyses conducted.

RESULTS

The median follow-up period was 18.2 months. Grade 1, 2, 3, and 4 acute toxicities were observed in 62.4%, 30.4%, 2.8%, and 0.6% of patients, respectively, with hematological toxicities accounting for all grade ≥ 3 acute toxicities. Grade 1, 2, 3, and 4 late toxicities occurred in 40.3%, 30.9%, 4.4%, and 1.7% of patients, respectively, with most grade ≥ 3 CIRT-induced late toxicities (72.7%) observed in patients receiving a CIRT dose ≥ 79.2 Gy. The median overall survival (OS) and progression-free survival (PFS) were 37.1 and 16.7 months, respectively. The 2-year locoregional control, OS, PFS, and distant metastasis-free survival rates were 66.1%, 64.2%, 40.3%, and 49.5%, respectively. Patients who received a CIRT dose ≤ 77 Gy had better OS (P = .047), but worse locoregional control compared with those who received higher doses (P = .026). Post-CIRT immunotherapy was an independent prognostic factor for improved OS, distant metastasis-free survival, and PFS (P = .002, P < .001, and P < .001, respectively).

CONCLUSIONS

CIRT with pencil beam scanning was effective for locally advanced NSCLC, resulting in acceptable toxicities and promising OS outcomes, particularly with doses of 69 to 77 Gy and post-CIRT immunotherapy.

Lnc-RAINY regulates genes involved in radiation susceptibility through DNA:DNA:RNA triplex-forming interactions and has tumor therapeutic potential in lung cancers

Lung cancer is the leading cause of cancer related deaths worldwide. Unfortunately, radiation resistance remains a major problem facing lung cancer patients. Recently, we identified a group of long non-coding RNAs (lncRNAs) known as linc-SPRY3 RNAs, expressed on the Y-chromosome, which play a role in radiation sensitivity by decreasing tumor burden in vitro and in vivo after radiation. In this study, we found that the linc-SPRY3 RNAs are one large lncRNA that we named Radiation Induced Y-chromosome linked long non-coding RNA (lnc-RAINY). Through ATAC-seq and immunoprecipitation experiments, we show that lnc-RAINY interacts with DNA in a triple helix to induce chromatin remodeling and gene expression. We also identified that lnc-RAINY regulates CDC6 and CDC25A expression affecting senescence induction, cell migration patterns, and cell cycle regulation. Furthermore, the administration of Lnc-RAINY encapsulated in FDA-approved nanoparticles into a lung cancer patient-derived xenograft model dramatically reduces tumor progression demonstrating therapeutic potential.

The effect and mechanism of atorvastatin regulating PI3K-Akt-mTOR pathway on radiosensitivity of hepatocellular carcinoma cells

Radiation therapy is an important method to treat liver cancer, but because of the strong DNA repair ability of liver cancer cells, even after receiving high doses of radiation still can not get satisfactory results. Atorvastatin (ATO) is a lipophilic and tissue-selective inhibitor of HMG-CoA reductase whose anticancer effects have been validated in various cells, but its effect on the radiation sensitivity of hepatocellular carcinoma cells remains unclear. Therefore, Therefore, this study explored the radiosensitivity of ATO and its possible mechanism by pretreating HepG2 with ATO and collecting HepG2 cells after irradiation. It was found that atorvastatin can not only affect the survival of liver cancer cells when used alone, but also enhance the radiation sensitivity of HepG2 cells. The study found that ATO significantly exacerbated the inhibitory effects of IR on the growth, proliferation, and migration of HepG2 cells. Measurement of ROS, SOD, GPx, and MDA levels indicated that ATO enhanced IR-induced oxidative stress, further promoted the decrease of Mitochondrial Membrane Potential, increased the rate of apoptosis in HepG2, upregulating pro-apoptotic proteins Bax and Cleaved-Caspase 3, and downregulating anti-apoptotic proteins Bcl-2. Western blot analysis showed that the PI3K-Akt-mTOR pathway was inhibited, leading to the activation of cytotoxic autophagy in HepG2 and an increase in the expression of the LC-3II protein. In summary, ATO, in combination with IR, enhances the oxidative stress response of HepG2 induced by IR, promotes autophagy by inhibiting the PI3K-Akt-mTOR pathway, and thereby potentially enhances the radiosensitivity of HepG2 as a pharmacological intervention.

Bioengineered Bacteriophage-Like Nanoparticles as RNAi Therapeutics to Enhance Radiotherapy against Glioblastomas

Since glioblastomas (GBMs) are radioresistant malignancies and most GBM recurrences occur in radiotherapy, increasing the effectiveness of radiotherapy by gene-silencing has recently attracted attention. However, the difficulty in precisely tuning the composition and RNA loading in nanoparticles leads to batch-to-batch variations of the RNA therapeutics, thus significantly restricting their clinical translation. Here, we bioengineer bacteriophage Qβ particles with a designed broccoli light-up three-way junction (b-3WJ) RNA scaffold (contains two siRNA/miRNA sequences and one light-up aptamer) packaging for the silencing of genes in radioresistant GBM cells. The in vitro results demonstrate that the cleavage of de novo designed b-3WJ RNA by Dicer enzyme can be easily monitored in real-time using fluorescence microscopy, and the TrQβ@b-3WJ_Let-7g^siEGFR successfully knocks down EGFR and IKKα simultaneously and thereby inactivates NF-κB signaling to inhibit DNA repair. Delivery of TrQβ@b-3WJ_Let-7g^siEGFR through convection-enhanced delivery (CED) infusion followed by 2Gy X-ray irradiation demonstrated that the median survival was prolonged to over 60 days compared with the 2Gy X-ray irradiated group (median survival: 31 days). Altogether, the results of this study could be critical for the design of RNAi-based genetic therapeutics, and CED infusion serves as a powerful delivery system for promoting radiotherapy against GBMs without evidence of systemic toxicity.

Emodin coupled with high LET neutron beam-a novel approach to treat on glioblastoma

The primary motivation of this investigative study is trying to find an alternative treatment that can be used to slow down or treat glioblastoma due to the witnessed toxic side effects of the current drugs coupled with limited effectiveness in overall treatment. Consequently, a Chinese plant extract emodin proves to play a critical role in this investigative study since results from the Western blot and the other accompanying assays for anti-cancer effects indicate that it cannot work a lot to suppress cell migration and possible invasion, but rather emodin can be combined with radiation to give desired outcomes. Our result shows that the kind of radiation which acts well with emodin is neutron radiation rather than gamma radiation. Emodin significantly enhanced the radiosensitivity of LN18 and LN428 cells to γ-rays through MTT assay and cell counting. Accordingly, exposure to neutron radiation in the presence of emodin induced apoptotic cell death and autophagic cell death to a significantly higher extent, and suppressed cell migration and invasiveness more robustly. These effects are presumably due to the ability of emodin to amplify the effective dose from neutron radiation more efficiently. Thus, the study below is one such trial towards new interventional discovery and development in relation to glioblastoma treatment.

Current progress of nanomedicine for prostate cancer diagnosis and treatment

Prostate cancer (PCa) is the most common new cancer case and the second most fatal malignancy in men. Surgery, endocrine therapy, radiotherapy and chemotherapy are the main clinical treatment options for PCa. However, most prostate cancers can develop into castration-resistant prostate cancer (CRPC), and due to the invasiveness of prostate cancer cells, they become resistant to different treatments and activate tumor-promoting signaling pathways, thereby inducing chemoresistance, radioresistance, ADT resistance, and immune resistance. Nanotechnology, which can combine treatment with diagnostic imaging tools, is emerging as a promising treatment modality in prostate cancer therapy. Nanoparticles can not only promote their accumulation at the pathological site through passive targeting techniques for enhanced permeability and retention (EPR), but also provide additional advantages for active targeting using different ligands. This property results in a reduced drug dose to achieve the desired effect, a longer duration of action within the tumor and fewer side effects on healthy tissues. In addition, nanotechnology can create good synergy with radiotherapy, chemotherapy, thermotherapy, photodynamic therapy and gene therapy to enhance their therapeutic effects with greater scope, and reduce the resistance of prostate cancer. In this article, we intend to review and discuss the latest technologies regarding the use of nanomaterials as therapeutic and diagnostic tools for prostate cancer.

Primary high-grade serous ovarian cancer cells are sensitive to senescence induced by carboplatin and paclitaxel in vitro

BACKGROUND

Various types of normal and cancer cells undergo senescence in response to carboplatin and paclitaxel, which are considered the gold standard treatments in ovarian cancer management. Surprisingly, the effect of these drugs on ovarian cancer cell senescence remained unknown.

METHODS

The experiments were conducted on primary high-grade serous ovarian cancer cells. Molecular markers of senescence were evaluated using cytochemistry and immunofluorescence. Cell cycle distribution was analyzed using flow cytometry. Expression of cyclins and signaling pathways was tested using western blot. Telomere length and telomerase activity were measured using qPCR, and the colocalization of telomeres with DNA damage foci using immuno-FISH. Oxidative stress-related parameters were quantified using appropriate fluorescence probes. Production of cancerogenic agents was analyzed using qPCR and ELISA.

RESULTS

Carboplatin applied with paclitaxel induces senescence of ovarian cancer cells in vitro. This activity was reflected by permanent G2/M growth arrest, a high fraction of cells expressing senescence biomarkers (SA-β-Gal and γ-H2A.X), upregulated expression of p16, p21, and p53 cell cycle inhibitors, and decreased expression of cyclin B1. Neither telomere length nor telomerase activity changed in the senescent cells, and the majority of DNA damage was localized outside telomeres. Moreover, drug-treated cancer cells exhibited increased production of STAT3 protein, overproduced superoxide and peroxides, and increased mitochondrial mass. They were also characterized by upregulated ANG1, CCL11, IL-6, PDGF-D, TIMP-3, TSP-1, and TGF-β1 at the mRNA and/or protein level.

CONCLUSIONS

Our findings imply that conventional chemotherapy may elicit senescence in ovarian cancer cells, which may translate to the development of a cancer-promoting phenotype, despite the inability of these cells to divide.

Therapeutic Efficacy of Carbon Ion Irradiation Enhanced by 11-MUA-Capped Gold Nanoparticles: An in vitro and in vivo Study

PURPOSE

Gold nanoparticles (AuNPs) are widely studied as radiosensitizers, but their radiosensitization in carbon ion radiotherapy is unsatisfactory. There is a lack of in vivo data on the radiosensitization of AuNPs under carbon ion irradiation. This study focused on the radiosensitization effect of AuNPs in the mouse melanoma cell line B16-F10 in vitro and in vivo.

MATERIALS AND METHODS

11-mercaptoundecanoic acid (11-MUA)-coated gold (Au) nanoparticles (mAuNPs) formulations were prepared and characterized. To verify the radiosensitization effect of mAuNPs, hydroxyl radicals were generated in aqueous solution, and the detection of intracellular reactive oxygen species (ROS) and clone survival were carried out in vitro. The tumor growth rate (TGR) and survival of mice were analyzed to verify the radiosensitization effect of mAuNPs in vivo. The apoptosis of tumor cells was detected, and the expression of key proteins in the apoptosis pathway was verified by immunohistochemistry.

RESULTS

The intracellular ROS level in B16-F10 cells was enhanced by mAuNPs under carbon ion irradiation. The sensitization rate of mAuNPs was 1.22 with a 10% cell survival rate. Compared with irradiation alone, the inhibitory effect of mAuNPs combined with carbon ion irradiation on tumor growth was 1.94-fold higher, the survival time of mice was prolonged by 1.75-fold, and the number of apoptotic cells was increased by 1.43-fold. The ratio of key proteins Bax and Bcl2 in the apoptosis pathway was up-regulated, and the expression of caspase-3, a key executor of the apoptosis pathway, was up-regulated.

CONCLUSION

In in vivo and in vitro experiments, mAuNPs showed radiosensitivity to carbon ion irradiation. The sensitization effect of mAuNPs on mice tumor may be achieved by activating the mitochondrial apoptosis pathway and increasing tumor tissue apoptosis. To our best knowledge, the present study is the first in vivo evidence for radiosensitization of mAuNPs in tumor-bearing mice exposed to carbon ion irradiation.

Application of Carbon Ion and Its Sensitizing Agent in Cancer Therapy: A Systematic Review

Carbon ion radiation therapy (CIRT) is the most advanced radiation therapy (RT) available and offers new opportunities to improve cancer treatment and research. CIRT has a unique physical and biological advantage that allow them to kill tumor cells more accurately and intensively. So far, CIRT has been used in almost all types of malignant tumors, and showed good feasibility, safety and acceptable toxicity, indicating that CIRT has a wide range of development and application prospects. In addition, in order to improve the biological effect of CIRT, scientists are also trying to investigate related sensitizing agents to enhance the killing ability of tumor cells, which has attracted extensive attention. In this review, we tried to systematically review the rationale, advantages and problems, the clinical applications and the sensitizing agents of the CIRT. At the same time, the prospects of the CIRT in were prospected. We hope that this review will help researchers interested in CIRT, sensitizing agents, and radiotherapy to understand their magic more systematically and faster, and provide data reference and support for bioanalysis, clinical medicine, radiotherapy, heavy ion therapy, and nanoparticle diagnostics.

The contrast agent 2,3,5-triiodobenzoic acid (TIBA) induces cell death in tumor cells through the generation of reactive oxygen species

The 2,3,5-triiodobenzoic acid (TIBA) is an iodine contrast agent used for visualization of tissue in X-ray techniques. However, TIBA induces physiological complications like increase in oxygen reactive species (ROS), and consequently, contrast-induced nephropathies. TIBA's antitumor activity was demonstrated in lung cancer, but the subcellular mechanisms involving its activity in tumor cells are still unknown. Thus, the objective of this work was evaluate whether the anti-tumor activity of TIBA involves ROS increase, in tumor lines of non-small cell lung cancer (H460), chronic myeloid leukemia (K562), and its cytotoxicity in normal renal epithelial (VERO). The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) assay was used for evaluation of cell viability, the H₂DCFDA (cell-permeant 2',7'-dichlorodihydrofluorescein diacetate) fluorescent probe to evaluate ROS induction, cell cycle analysis was performed using flow cytometry to measure cell death, and immunofluorescence with annexin/7-AAD (7-amino-actinomycin D), to assess the association of cell death with the ROS generation. TIBA decreases cell viability in a dose-dependent manner for the H460 and K562. However, VERO cells showed less response to the drug, with 70% viable cells after 72 h of treatment in the highest concentration of the drug. While the tumor cells with only 20% viable cells. Besides, tumor cells exhibited higher DNA fragmentation, compared to the renal line (VERO with 5% of fragmented DNA, H460 with 26%, and 56% in K562). Finally, TIBA-induced ROS increase and apoptosis in all lines, which is significantly decreased after treatment with the antioxidant N-acetyl-cysteine (NAC). These data demonstrate the relationship between the increased cellular oxidative stress and the anti-tumor action of the TIBA.

Inhibition of Wnt signalling pathway by XAV939 enhances radiosensitivity in human cervical cancer HeLa cells

Cervical cancer is the second most common malignant tumour threatening women's health. In recent years, heavy-ion beam therapy is becoming a newly emerging therapeutic mean of cancer; however, radio-resistance and radiation-induced damage constitute the main obstacles for curative treatment of cervical cancer. Therefore, to identify the radiosensitizers is essential. Here, we investigated the effects of Wnt signalling pathway on the response of ¹²C⁶⁺ radiation in HeLa cells. XAV939, an inhibitor of Wnt signalling pathway, was added two hours before ¹²C⁶⁺ radiation.¹²C⁶⁺ radiation inhibited the viability of HeLa cells in a time-dependent manner, and inhibiting Wnt signalling using XAV939 significantly intensified this stress. Meanwhile, ¹²C⁶⁺ radiation induced a significant increased cell apoptosis, G2/M phase arrest, and the number of γ-H2AX foci. Supplementation with XAV939 significantly increased the effects induced by ¹²C⁶⁺ radiation alone. Combining XAV939 with ¹²C⁶⁺ irradiation, the expression of apoptotic genes (p53, Bax, Bcl-2) was significantly increased, while the expression of Wnt-related genes (Wnt3a, Wnt5a, β-catenin, cyclin D1 and c-Myc) was significantly decreased. Overall, these findings suggested that blockage of the Wnt/β-catenin pathway effectively sensitizes HeLa cells to ¹²C⁶⁺ irradiation, and it may be a potential therapeutic approach in terms of increasing the clinical efficacy of ¹²C⁶⁺ beams.

Cellular Responses to Platinum-Based Anticancer Drugs and UVC: Role of p53 and Implications for Cancer Therapy

Chemotherapy is intended to induce cancer cell death through apoptosis and other avenues. Unfortunately, as discussed in this article, moderate doses of genotoxic drugs such as cisplatin typical of those achieved in the clinic often invoke a cytostatic/dormancy rather than cytotoxic/apoptosis response in solid tumour-derived cell lines. This is commonly manifested by an extended apoptotic threshold, with extensive apoptosis only being seen after very high/supralethal doses of such agents. The dormancy response can be associated with senescence-like features, polyploidy and/or multinucleation, depending in part on the p53 status of the cells. In most solid tumour-derived cells, dormancy represents a long-term survival mechanism, ultimately contributing to disease recurrence. This review highlights the nonlinearity of key aspects of the molecular and cellular responses to bulky DNA lesions in human cells treated with chemotherapeutic drugs (e.g., cisplatin) or ultraviolet light-C (a widely used tool for unraveling details of the DNA damage-response) as a function of the level of genotoxic stress. Such data highlight the growing realization that targeting dormant cancer cells, which frequently emerge following conventional anticancer treatments, may represent a novel strategy to prevent or, at least, significantly suppress cancer recurrence.

Downregulated Mucin 1 alleviates paclitaxel resistance in non‑small cell lung cancer cells

Multidrug resistance of non‑small cell lung cancer (NSCLC) is a common clinical problem, which is one of the main reasons leading to the failure of chemotherapy. Therefore, how to overcome or prevent drug resistance has become a hot and difficult issue in clinical research. The present study was designed to investigate the expression patterns, functions and underlying mechanisms of MUC1 in regulating paclitaxel‑resistant cell line A549/PR in NSCLC. RT‑qPCR and western blot was performed to determine the mRNA and protein level, respectively. CCK‑8 was conducted to determine the cell viability of A549/PR cells. Moreover, flow cytometry assay was applied to examine the apoptosis rate of A549/PR. Herein, the MUC1 was over‑expressed in clinic NSCLC tissues and A549/PR cells. Silence of MUC1 could obviously suppress the proliferation and promote apoptosis of A549/PR cells in treatment of paclitaxel through up‑regulating the expression of Bax and Caspase‑3, and down‑regulating the expression of Bcl‑2, suggesting that chemotherapy combined with the modulation of MUC1 might be characterized as a promising therapeutic approach to overcome paclitaxel‑resistance in NSCLC in the future.

Significance of concurrent use of weekly cisplatin in carbon-ion radiotherapy for locally advanced adenocarcinoma of the uterine cervix: A propensity score-matched analysis

BACKGROUND

Although carbon-ion radiotherapy (C-ion RT) with concurrent chemotherapy (chemo-C-ion RT) is a promising treatment for adenocarcinoma (AC) of the uterine cervix, its long-term efficacy remains unclear. We evaluated the long-term significance of concurrent weekly cisplatin and C-ion RT for locally advanced AC of the uterine cervix.

METHODS

We performed a pooled analysis of patients with stage IIB-IVA AC of the uterine cervix who underwent C-ion RT alone or chemo-C-ion RT between September 2007 and December 2018 at our institution. Patients received 74.4 Gy (relative biological effectiveness) with or without cisplatin (40 mg/m² per week for up to 5 weeks), underwent no prior pelvic RT or systemic therapy, and had a performance status of 0-2. Propensity score matching was based on the year of diagnosis, regional lymph node metastasis, and stage.

RESULTS

The matched cohort contained 26 patients who underwent C-ion RT and 26 who underwent chemo-C-ion RT. The median age and follow-up period were 57 (range, 28-79) years and 34 (range, 2-126) months, respectively. The 5-year overall survival rate was significantly better in the chemo-C-ion RT group (72%) than in the C-ion RT group (46%; P = .041). The 5-year distant metastatic-free rate was also significantly better in the chemo-C-ion RT group (66%) than in the C-ion RT group (41%; P = .048). The incidence of grade ≥ 3 late toxicities was comparable between the two groups.

CONCLUSIONS

Chemo-C-ion RT for locally advanced AC of the uterine cervix is associated with a long-term survival benefit.

Radiosensitizing Effect of Gadolinium Oxide Nanocrystals in NSCLC Cells Under Carbon Ion Irradiation

Gadolinium-based nanomaterials can not only serve as contrast agents but also contribute to sensitization in the radiotherapy of cancers. Among radiotherapies, carbon ion irradiation is considered one of the superior approaches with unique physical and biological advantages. However, only a few metallic nanoparticles have been used to improve carbon ion irradiation. In this study, gadolinium oxide nanocrystals (GONs) were synthesized using a polyol method to decipher the radiosensitizing mechanisms in non-small cell lung cancer (NSCLC) cell lines irradiated by carbon ions. The sensitizer enhancement ratio at the 10% survival level was correlated with the concentration of Gd in NSCLC cells. GONs elicited an increase in hydroxyl radical production in a concentration-dependent manner, and the yield of reactive oxygen species increased obviously in irradiated cells, which led to DNA damage and cell cycle arrest. Apoptosis and cytostatic autophagy were also significantly induced by GONs under carbon ion irradiation. The GONs may serve as an effective theranostic material in carbon ion radiotherapy for NSCLC.

Is there a role for carbon therapy in the treatment of gynecological carcinomas? A systematic review

This Systematic Review summarizes the literatures of clinical trials on the efficacy and safety of carbon ion therapy for gynecological carcinomas. The protocol is detailed in the online PROSPERO database, registration no. CRD42019121424, and a final set of eight studies were included. In the treatment of cervical carcinomas, both carbon ion therapy alone and carbon ion therapy concurrent chemotherapy have presented good efficacy. Besides, the efficacy of inoperable endometrial carcinomas and gynecological melanoma are similar to that of surgical treatment. In terms of safety, gastrointestinal and genitourinary toxicities are low and could be controlled by limiting the volume and dose of intestinal tract and bladder. Carbon ion radiotherapy could be considered a safe, effective and feasible therapy for gynecological carcinomas.

Overcoming radioresistance in WiDr cells with heavy ion irradiation and radiosensitization by 2-deoxyglucose with photon irradiation

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2-DG acts as a radiosensitizer to photons depending on the time of its application.

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There is no sensitization to ¹²C irradiation by 2-DG.

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¹²C combination therapy still has the higher dose effectiveness.

Background and purpose

Radiosensitizers and heavy ion irradiation could improve therapy for female patients with malignant tumors located in the pelvic region through dose reduction. Aim of the study was to investigate the radiosensitizing potential of 2-deoxy-d-glucose (2-DG) in combination with carbon ion-irradiation (¹²C) in representative cell lines of cancer in the female pelvic region.

Materials and methods

The human cervix carcinoma cell line CaSki and the colorectal carcinoma cell line WiDr were used. 2-DG was employed in two different settings, pretreatment and treatment simultaneous to irradiation. Clonogenic survival, α and β values for application of the linear quadratic model and relative biological effectiveness (RBE) were determined. ANOVA tests were used for statistical group comparison. Isobolograms were generated for curve comparisons.

Results

The comparison of monotherapy with ¹²C versus photons yielded RBE values of 2.4 for CaSki and 3.5 for WiDr along with a significant increase of α values in the ¹²C setting. 2-DG monotherapy reduced the colony formation of both cell lines. Radiosensitization was found in WiDr for the combination of photon irradiation with synchronous application of 2-DG. The same setup for ¹²C showed no radiosensitization, but rather an additive effect. In all settings with CaSki, the combination of irradiation and 2-DG exhibited additive properties.

Conclusion

The combination of 2-DG and photon therapy, as well as irradiation with carbon ions can overcome radioresistance of tumor cells such as WiDr.

Enhanced Radiosensitization by Gold Nanoparticles with Acid-Triggered Aggregation in Cancer Radiotherapy

An ideal radiosensitizer holding an enhanced tumor retention can play an incredible role in enhancing tumor radiotherapy. Herein, a strategy of acid-triggered aggregation of small-sized gold nanoparticles (GNPs) system within tumor is proposed and the resulting GNPs aggregates are applied as a radiosensitizer in vitro and in vivo. The GNPs system with the acid-triggered aggregation achieves an enhanced GNPs accumulation and retention in cancer cells and tumors in the form of the resulted GNPs aggregates. As a consequence, the radiosensitization effect shows significant improvement in cancer radiotherapy, which is shown in the studies of DNA breakage and the comet assay, and the sensitizer enhancement ratio (SER) value of the GNPs system (1.730) with MCF-7 cancer cells is much larger than that of the single GNPs (1.16). In vivo antitumor studies reveal that the GNPs system also enhances the sensitivity of MCF-7 tumor xenograft to radiotherapy. Furthermore, the GNPs aggregates improve the signal of small GNPs in vivo photoacoustic imaging. This study provides a new strategy and insights into fabricating nanoaggregates to magnify the radiosensitive efficiency of nanosystems in cancer radiotherapy.

Enhanced Radiosensitization by Gold Nanoparticles with Acid-Triggered Aggregation in Cancer Radiotherapy

An ideal radiosensitizer holding an enhanced tumor retention can play an incredible role in enhancing tumor radiotherapy. Herein, a strategy of acid-triggered aggregation of small-sized gold nanoparticles (GNPs) system within tumor is proposed and the resulting GNPs aggregates are applied as a radiosensitizer in vitro and in vivo. The GNPs system with the acid-triggered aggregation achieves an enhanced GNPs accumulation and retention in cancer cells and tumors in the form of the resulted GNPs aggregates. As a consequence, the radiosensitization effect shows significant improvement in cancer radiotherapy, which is shown in the studies of DNA breakage and the comet assay, and the sensitizer enhancement ratio (SER) value of the GNPs system (1.730) with MCF-7 cancer cells is much larger than that of the single GNPs (1.16). In vivo antitumor studies reveal that the GNPs system also enhances the sensitivity of MCF-7 tumor xenograft to radiotherapy. Furthermore, the GNPs aggregates improve the signal of small GNPs in vivo photoacoustic imaging. This study provides a new strategy and insights into fabricating nanoaggregates to magnify the radiosensitive efficiency of nanosystems in cancer radiotherapy.

Comprehensive review on how platinum- and taxane-based chemotherapy of ovarian cancer affects biology of normal cells

One of the most neglected aspects of chemotherapy are changes, and possible consequences of these changes, that occur in normal somatic cells. In this review, we summarize effects of selected drugs used to treat ovarian cancer (platin derivatives-cisplatin and carboplatin; and taxanes-paclitaxel and docetaxel) on cellular metabolism, acquisition of reactive stroma features, cellular senescence, inflammatory reactions, apoptosis, autophagy, mitophagy, oxidative stress, DNA damage, and angiogenesis in various types of normal cells, including fibroblasts, epithelial cells, endothelial cells, and neurons. The activity of these drugs against the normal cells is presented from a broader perspective of their desirable anti-tumoral effects.

Transition metal compounds as cancer radiosensitizers

Combining metallo-drugs with ionising radiation for synergistic cancer cell killing: chemical design principles, mechanisms of action and emerging applications.

Whole-Body 12C Irradiation Transiently Decreases Mouse Hippocampal Dentate Gyrus Proliferation and Immature Neuron Number, but Does Not Change New Neuron Survival Rate

High-charge and -energy (HZE) particles comprise space radiation and they pose a challenge to astronauts on deep space missions. While exposure to most HZE particles decreases neurogenesis in the hippocampus—a brain structure important in memory—prior work suggests that ¹²C does not. However, much about ¹²C’s influence on neurogenesis remains unknown, including the time course of its impact on neurogenesis. To address this knowledge gap, male mice (9–11 weeks of age) were exposed to whole-body ¹²C irradiation 100 cGy (IRR; 1000 MeV/n; 8 kEV/µm) or Sham treatment. To birthdate dividing cells, mice received BrdU i.p. 22 h post-irradiation and brains were harvested 2 h (Short-Term) or three months (Long-Term) later for stereological analysis indices of dentate gyrus neurogenesis. For the Short-Term time point, IRR mice had fewer Ki67, BrdU, and doublecortin (DCX) immunoreactive (+) cells versus Sham mice, indicating decreased proliferation (Ki67, BrdU) and immature neurons (DCX). For the Long-Term time point, IRR and Sham mice had similar Ki67+ and DCX+ cell numbers, suggesting restoration of proliferation and immature neurons 3 months post-¹²C irradiation. IRR mice had fewer surviving BrdU+ cells versus Sham mice, suggesting decreased cell survival, but there was no difference in BrdU+ cell survival rate when compared within treatment and across time point. These data underscore the ability of neurogenesis in the mouse brain to recover from the detrimental effect of ¹²C exposure.

Sensitization of Cancer Cells to Radiation and Topoisomerase I Inhibitor Camptothecin Using Inhibitors of PARP and Other Signaling Molecules

Radiation and certain anticancer drugs damage DNA, resulting in apoptosis induction in cancer cells. Currently, the major limitations on the efficacy of such therapies are development of resistance and adverse side effects. Sensitization is an important strategy for increasing therapeutic efficacy while minimizing adverse effects. In this manuscript, we review possible sensitization strategies for radiation and anticancer drugs that cause DNA damage, focusing especially on modulation of damage repair pathways and the associated reactions.

Clinical outcomes of carbon ion radiotherapy with concurrent chemotherapy for locally advanced uterine cervical adenocarcinoma in a phase 1/2 clinical trial (Protocol 1001)

We conducted a phase 1/2 study to evaluate the efficacy and safety of carbon ion radiotherapy (C-ion RT) with concurrent chemotherapy for locally advanced uterine cervical adenocarcinoma. Thirty-three patients were enrolled between April 2010 and March 2014. Treatment consisted of C-ion RT with concurrent weekly cisplatin at a dose of 40 mg/m² . In the phase 1 component, the total dose was escalated from 68.0 Gy (relative biological effectiveness [RBE]) to 74.4 Gy (RBE) to determine the maximum tolerated dose of C-ion RT. In the phase 2 component, the efficacy and safety of C-ion RT with concurrent chemotherapy were evaluated using the dose determined in the phase 1 component. The median follow-up duration was 30 months. Two patients did not receive chemotherapy because of anemia or leukocytopenia immediately prior to commencing treatment; 31 patients were analyzed. None of the patients developed dose-limiting toxicities. The recommended dose (RD) was determined to be 74.4 Gy (RBE). In the phase 2 component, two patients developed Grade 3-4 toxicities in the gastrointestinal tract, due to repeated laser coagulation or peritonitis caused by appendicitis. In the patients treated with the RD, the 2-year local control, progression-free survival, and overall survival rates were 71%, 56%, and 88%, respectively. C-ion RT with concurrent weekly cisplatin was well tolerated in patients with locally advanced uterine cervical adenocarcinoma. Our findings support further investigations into the efficacy of this strategy.

Comparison of human lung cancer cell radiosensitivity after irradiations with therapeutic protons and carbon ions

The aim of this study was to investigate effects of irradiations with the therapeutic proton and carbon ion beams in two non-small cell lung cancers, CRL5876 adenocarcinoma and HTB177 large cell lung carcinoma. The DNA damage response dynamics, cell cycle regulation, and cell death pathway activation were followed. Viability of both cell lines was lower after carbon ions compared to the therapeutic proton irradiations. HTB177 cells showed higher recovery than CRL5876 cells seven days following the treatments, but the survival rates of both cell lines were lower after exposure to carbon ions with respect to therapeutic protons. When analyzing cell cycle distribution of both CRL5876 and HTB177 cells, it was noticed that therapeutic protons predominantly induced G1 arrest, while the cells after carbon ions were arrested in G2/M phase. The results illustrated that differences in the levels of phosphorylated H2AX, a double-strand break marker, exist after therapeutic proton and carbon ion irradiations. We also observed dose- and time-dependent increase in the p53 and p21 levels after applied irradiations. Carbon ions caused larger increase in the quantity of p53 and p21 compared to therapeutic protons. These results suggested that various repair mechanisms were induced in the treated cells. Considering the fact that we have not observed any distinct change in the Bax/Bcl-2 ratio following irradiations, it seemed that different types of cell death were involved in the response to the two types of irradiations that were applied.

Translational Research to Improve the Efficacy of Carbon Ion Radiotherapy: Experience of Gunma University

Carbon ion radiotherapy holds great promise for cancer therapy. Clinical data show that carbon ion radiotherapy is an effective treatment for tumors that are resistant to X-ray radiotherapy. Since 1994 in Japan, the National Institute of Radiological Sciences has been heading the development of carbon ion radiotherapy using the Heavy Ion Medical Accelerator in Chiba. The Gunma University Heavy Ion Medical Center (GHMC) was established in the year 2006 as a proof-of-principle institute for carbon ion radiotherapy with a view to facilitating the worldwide spread of compact accelerator systems. Along with the management of more than 1900 cancer patients to date, GHMC engages in translational research to improve the treatment efficacy of carbon ion radiotherapy. Research aimed at guiding patient selection is of utmost importance for making the most of carbon ion radiotherapy, which is an extremely limited medical resource. Intratumoral oxygen levels, radiation-induced cellular apoptosis, the capacity to repair DNA double-strand breaks, and the mutational status of tumor protein p53 and epidermal growth factor receptor genes are all associated with X-ray sensitivity. Assays for these factors are useful in the identification of X-ray-resistant tumors for which carbon ion radiotherapy would be beneficial. Research aimed at optimizing treatments based on carbon ion radiotherapy is also important. This includes assessment of dose fractionation, normal tissue toxicity, tumor cell motility, and bystander effects. Furthermore, the efficacy of carbon ion radiotherapy will likely be enhanced by research into combined treatment with other modalities such as chemotherapy. Several clinically available chemotherapeutic drugs (carboplatin, paclitaxel, and etoposide) and drugs at the developmental stage (Wee-1 and heat shock protein 90 inhibitors) show a sensitizing effect on tumor cells treated with carbon ions. Additionally, the efficacy of carbon ion radiotherapy can be improved by combining it with cancer immunotherapy. Clinical validation of preclinical findings is necessary to further improve the treatment efficacy of carbon ion radiotherapy.